90% of all patients with achlorhydria have detectable antibodies against the H+/K+ ATP-ase proton pump. The diagnosis is made if the gastric pH remains high (>4.0) despite maximum pentagastrin stimulation. High gastrin levels are often detected.
Achlorhydria and hypochlorhydria may lead to microbial overgrowth since the disinfectant qualities of gastric acid are diminished. This can increase the risk of infections in the digestive tract (such as Vibrio or Helicobacter infections).
Treatment focuses on addressing the underlying cause, injection of vitamins like vitamin B12 (which is poorly absorbed in the absence of intrinsic factor) in autoimmune disorders, and avoiding foods that may have a high microbial load.